MISCELLANEOUS NOTES. 201 



Time will no doubt revolutionize all our present standards, and birds we 

 have hitherto considered as absolutely distinct species, will be found to be 

 variable phases of one. and the same; and others, which we now consider 

 simply local types, will be given specific, if not generic, rank, for there is 

 undoubtedly much yet to learn with regard to even our commonest species. 

 Orthodoxy iu questions relating to Natural History appears to be a mistake, 

 and many of our long-cherished illusions, based upon the precepts and 

 theories of irrefutable authorities, crumble and fall to the ground year after 

 year, and the more one sees of nature and her ways, the less inclined does 

 one feel either to lay down standards for oneself, or accept those of others 

 without due consideration. 



C. H. DONALD, f.z.s. 

 Bhadarwa, 31s* May 1907. 



No. XVIII— A VISIT TO SOUTH SENTINEL ISLAND. 



On February 16th I managed to land on the interesting and unfrequented 

 island of South Sentinel in company with Mr. P. F. Wickham. The object 

 of our visit was if possible to observe the nesting habits of the Pied Imperial 

 and Nicobar Hackled Pigeons. 



I had obtained the young of both these pigeons on this island in March of 

 the previous year, so felt confident we should get the eggs. 



South Sentinel is a coral island about a mile long by half a mile broad 

 situated in north latitude 11°, about 17 miles N.-W. of the Little Andaman. 

 It is out of sight of land and a landing can only be effected in calm weather. 

 The highest point of the island is only about 10 feet above high tide level 

 and its centre is occupied by a swamp, the water of which is brackish. 



The whole island, with the exception of the swamp, is covered with dense 

 forest, consisting mainly of mohwa trees (Mimusops littoralis) with an under- 

 growth of various smaller trees and shrubs. There is a well-defined sea fence 

 along the shore consisting of screw pines (Pandanus sp.) and Hibiscus. 



In places the mohwa trees are of very large dimensions, but are hollow and 

 evidently long past maturity. It is in the hollows of these huge trees that the 

 celebrated Robber Crab (Birgus latro) makes his home. This small island is the 

 only one of all the Andaman group in which this giant hermit crab is found. 

 He is of a fiue purplish blue colour and measures about 2 feet across (legs 

 extended) and turns the scale at upwards of 51bs. He has no protecting shell, 

 for the very good reason that there is no shell large enough to house him and 

 like other hermit crabs he cannot make his own shell. He is nocturnal in his 

 habits, coming out of his arboreal retreat shortly before sundown, and feeding 

 on various jungle fruits. He is an adept at climbing, but so far as my 

 experience goes they feed chiefly, if not entirely, on fallen fruits. Some I 

 kept in captivity were very fond of cocoanuts and papayas. 



They have two unequal very powerful nippers, and woe betide the incau- 

 tious person who allows the animal to close them upon his finger, for he will 

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